BACKGROUND/AIMS: Experimental studies have suggested that trypsinogen may enhance tumor progression and that the ratio between anionic trypsinogen and cationic trypsinogen (HAT/HCT) and between the sum of trypsinogens and pancreatic secretory trypsin inhibitor (PSTI) ((HAT + HCT)/PSTI) are disturbed in patients with pancreatic cancer. The aim of this study was to investigate if pre-diagnostic levels of these parameters are associated with subsequent pancreatic cancer risk. METHODS: A total of 33,346 subjects participated in a health screening programme in Malmö, Sweden. Pancreatic cancer cases (n = 84) were matched to three controls each. HAT, HCT and PSTI were analyzed in pre-diagnostic serum samples. Odds ratios for pancreatic cancer were calculated using logistic regression and were then stratified for other risk factors. RESULTS: In the main analysis, a statistically significant association between the ratio between HAT/HCT and pancreatic cancer was observed for all, for the crude OR and for the ORs adjusted for sex, BMI or Helicobacter pylori. When stratified for sex, statistically significant associations were found for females in the crude OR and for the ORs adjusted for time to analysis, BMI, alcohol consumption or H. pylori. There was a positive association between the ratio of HAT/HCT to pancreatic cancer in the intermediate/high alcohol consumption group and subjects with a BMI